One vertex per element, one color per generator, with an edge from x to x·s.
(9,10,14,15)(11,19,20,16)(12,17,22,21)(13,23,24,18)(25,26)(27,32)(28,29)(30,34)(31,35)(33,40)(36,39)(37,38)(1,2)(3,6)(4,5)(7,8)(10,15)(12,22)(16,19)(18,23)(27,35)(31,32)(36,38)(37,39) involution — undirected(2,5)(3,7)(10,15)(11,20)(12,22)(13,24)(25,27,30,35)(26,31,34,32)(28,38,33,36)(29,39,40,37)(1,3,4,7)(2,6,5,8)(9,11,14,20)(10,16,15,19)(12,23,22,18)(13,21,24,17)(25,28,30,33)(26,29,34,40)(27,36,35,38)(31,37,32,39)(1,3)(2,6)(4,7)(5,8)(9,12)(10,17)(11,18)(13,19)(14,22)(15,21)(16,24)(20,23)(25,27)(26,32)(28,38)(29,37)(30,35)(31,34)(33,36)(39,40) involution — undirected(1,2)(3,6)(4,5)(7,8)(9,13,14,24)(10,18,15,23)(11,21,20,17)(12,19,22,16)(25,29)(26,33)(27,37)(28,34)(30,40)(31,38)(32,36)(35,39)A Cayley diagram is a choice, not a fact about the group. Another drawing of this group — in a book, or on a different generating set — may look nothing like this one.